sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale), Color: Reddish-brown, earthy tones, Luster: Waxy to dull, Crystal structure: Trigonal/Microcrystalline, Cleavage: None/Conchoidal fracture, Specific gravity: 2.58-2.91

Hardness: 6

Identified April 3, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: Reddish-brown, earthy tones, Luster: Waxy to dull, Crystal structure: Trigonal/Microcrystalline, Cleavage: None/Conchoidal fracture, Specific gravity: 2.58-2.91

Formation & geological history

Formed through the deposition of silica from water or hydrothermal fluids, often in volcanic or sedimentary environments. It is an opaque variety of chalcedony that gains its color from iron inclusions.

Uses & applications

Used in gemstone carvings, jewelry (cabochons), interior decoration, and as a popular specimen for rock tumbling and collection.

Geological facts

Jasper has been used as a gemstone since antiquity; it was known in ancient Greek, Roman, and Hebrew literature. It is often referred to as the 'Supreme Nurturer' in metaphysical circles.

Field identification & locations

Identify by its opacity (unlike translucent agate) and conchoidal fracture. Found worldwide, frequently in riverbeds or coastal deposits. Tips: Test for hardness against steel; jasper will scratch common glass.